Jugement Day
Many governments are assessing the quality of university research, much to the dismay of some researchers.
Réussir ses études de mathématiques
Entre toutes les passions de l’esprit humain, l’une des plus violentes, c’est le désir de savoir» Bossuet(1).
La greffe d’organes en Algérie état des lieux et proposition d’un plan national de greffe
La greffe d’organes constitue une thérapeutique qui consiste à remplacer un organe non fonctionnel par un organe prélevé sur un donneur qui peut être décédé ou en état de mort encéphalique, dit «à cœur battant». Il s’agit de prélèvements multi-organes (PMO ) et de tissus : rein, foie, cœur, poumons, pancréas, intestin pour les organes et os, cornée, peau, pour les tissus. Ce type de donneurs représente l’essentiel de l’activité de greffe dans de nombreux pays.
Bioéthique
THE VIRTUAL LAB Confronted with the explosive popularity of online learning, researchers are seeking new ways to teach the practical skills of science.
Next-Generation Sequencing: Methodology and Application
Première Solution pour faire des spermatozoïdes artificiel (Découverte par les japonais, perspective pour une solution a la stérilité)
A Plant Evolution Revolution
Mycorrhizal Fungi Expand Contemporary Cropping Opportunities by Mike Amaranthus, Ph.D. & Larry Simpson
Soil biology has emerged over the last decade as a critical part of the knowledge base for successful and sustainable agricultural production. A key component of biology is the profound plant/mycorrhizal fungi relationship, which has enormous potential for improved management of contemporary farming systems. Although using these fungi has the potential to revolutionize agriculture they are certainly not new in terms of the evolution of plants.
Where we’ve been The fossil evidence indicates that the specialized “mycorrhiza” (meaning “fungus-root”) plant relationship dates back over 460 million years and actually played a key role in allowing plants to utilize terrestrial habitats. Without A healthy mycorrhizalinoculated organic winter wheat field in Canada.
mycorrhizal fungi, today’s crop plants might not exist, unless you are farming seaweed! For the first 75 million years that plants colonized dry Since before World War II, scientific and technological advances land, they did not have differentiated root tissue and depended in agronomy have focused primarily on the development of entirely on this symbiotic relationship with mycorrhizal fungi to
chemical and mechanical approaches to improving crop producaccess nutrients and moisture from the various and often harsh tion yields. Nutrient needs have been addressed using synthetic terrestrial environments. The root structures of plants actually fertilizers while weed suppression has been accomplished through evolved specifically as specialized attachment sites to better actillage and herbicides and plant diseases controlled using an array commodate these fungi and the efficiencies available through of chemical pesticides. More recently, modern science has begun the symbiotic “trading” of water and nutrients for sugars proto understand that in natural habitat plant roots are a complex duced by photosynthesis.
mixture of both fungi and plant that is fundamental to life on the In this symbiosis, the plant is provided better access to and planet. The vast majority of crops form an association with these uptake of nutrients and water from the soil. In return, the specialized mycorrhizal soil fungi in order to maximize perforfungus, which cannot synthesize its own nourishment, receives mance. Among the few but notable exceptions are members of its energy source in the form of carbohydrates donated by the the Brassicaceae plant family (cabbage, broccoli, cauliflower, radplant. This highly successful system continues in 90 percent of ish, turnips, canola, etc.) the Amaranthaceae plant family (beets, plant species today. spinach, chard, etc.) and the Polygonaceae plant family (rhubarb, Agricultural science has only in the last decade begun to recogbuckwheat). Virtually all other crop plants worldwide are meant nize the importance of mycorrhizal fungi in farming ecosystems. to host some form of mycorrhizal association.
Conséquence d’un changement climatique dans la région Les menaces d’une eau plus rare dans les pays arabes
Il n’y a pas que l’assèchement du sous-sol qui regorge de pétrole et gaz qui doit désormais donner à réfléchir aux dirigeants arabes, pourtant peu soucieux, eux-mêmes, des ravages de la mauvaise gouvernance dont ils sont responsables devant l’histoire.
Sahara : pourquoi il vaut mieux exploiter le soleil plutôt que l'eau
Une étude vient de le confirmer : les eaux souterraines du Sahara sont bien renouvelables. Mais de manière si infime que l'exploitation qui en est faite depuis les années 1960, et qui augmentera de manière dramatique avec l'exploitation du gaz de schiste, menace pour de bon l'or bleu du Sahara.





